Research Projects

Cancel
  • EmitterPlus

    Integrated Process for Formation of Gas-Phase Emitters and Selective Contacts

    © Fraunhofer ISE

    Schematic representation of the solar cell structure with RVD emitter on the front and passivating contact on the back.

    In the project “EmitterPlus”, gas phase emitters (RVD: rapid vapor-phase direct doping) are investigated as an alternative to conventional emitters in solar cells with selective contacts (TOPCon: tunnel oxide passivated contacts). The aim is to develop an integrated process for emitter diffusion and annealing of the selective contacts, with which solar cells can be produced with an efficiency of 25%. For this purpose, existing processes will be adapted and further developed. In addition to the demonstration of highly efficient solar cells, the process and machine know-how necessary for an industrial implementation of the gas phase emitter process will be generated in order to subsequently develop the industrial implementation together with machine builders. | Duration: 06/2018 - 05/2020

    more info
  • © Fraunhofer ISE

    Simulated current transport in a locally contacted solar cell (left) and in a solar cell with the newly developed passivated TOPCon base contact (right).

    Due to ongoing improvements in material quality and surface passivation, recombination at the metal contacts has become one of the dominant loss mechanisms in silicon solar cells. This loss can be reduced by usingso-called passivated contacts, which suppress the recombination of minority charge carriers and simultaneously allow lossless majority charge carrier transport. On the basis of an extremely thin dielectric tunnel oxide, we have succeeded in producing a very effective, passivated contact (TOPCon), which simultaneously passivates the surface excellently and constitutes low resistance to charge carrier transport. | Duration: 07/2011 - 06/2015

    more info
  • LED-based module simulator with adjustable excitation spectrum for precise IV measurement of PV modules.
    © Fraunhofer ISE

    LED-based module simulator with adjustable excitation spectrum for precise IV measurement of PV modules.

    Project in the Business Area: Photovoltaics, Topic: Silicon Photovoltaics, Perovskite and Organic Photovoltaics; Field of Work: Perovskite Silicon Tandem Photovoltaics, High-Efficiency Silicon Cell Fabrication and Analysis; Duration: 02/2021 - 01/2024

    more info
  • SEM-Aufnahme einer Perowskit-Silizium-Tandemsolarzelle auf texturiertem Silizium. Der Perowskit-Absorber wurde mittels Verdampfung der anorganischen Komponenten und anschließender nasschemischer Infiltration der organischen Komponenten hergestellt.
    © Fraunhofer ISE

    SEM-Aufnahme einer Perowskit-Silizium-Tandemsolarzelle auf texturiertem Silizium. Der Perowskit-Absorber wurde mittels Verdampfung der anorganischen Komponenten und anschließender nasschemischer Infiltration der organischen Komponenten hergestellt.

    In order to produce perovskite layers of the highest quality for perovskite-silicon tandem solar cells, we are pursuing a hybrid route combining vacuum evaporation and solution deposition. The two processes complement each other perfectly to enable the deposition of perovskite layers on micrometer-sized silicon pyramids. This has enabled us to achieve efficiencies of over 32%. We are now transferring this technology to our Pero-Si-SCALE technology platform using industrially scalable equipment for full wafer sizes (M12). | Laufzeit: 05/2023 - 04/2026

    more info
  • Neben dem Übertrag auf größere Substrate werden auch neue kostengünstige Prozesse wie Inkjet-Druck erprobt, um die Herstellung der III-V//Si-Tandemsolarzellen wirtschaftlicher zu machen.
    © Fraunhofer ISE / Foto: Dirk Mahler

    In addition to the transfer to larger substrates, new cost-effective processes such as inkjet printing are also being tested in order to make the production of III-V//Si tandem solar cells more economical.

    Tandem photovoltaics is one of the fastest developing fields of solar research today. In industry today, single-junction silicon solar cells are the state of the art. At Fraunhofer ISE, it has already been demonstrated that using layers of III-V compound semiconductors the Auger limit of silicon, which is 29.4% efficiency, can be surpassed. The most recent record is 36.1% (2023). The task now is to make the manufacturing processes required to produce these III-V//Si tandem solar cells more cost-effective and efficient and to scale them up further. The first goal of small series production is to realize a module prototype with an efficiency of more than 30%. | Duration: 01/2023 - 12/2025

    more info
  • Nano-Tandem - Large-area structurization
    © Fraunhofer ISE

    Large-area structurization of a template realized with nanoimprint lithography for the deposition of III-V nanowires on a silicon wafer of 100 mm diameter. Photo (right): Electron microscope image of the structurized surface. The resist columns of 200 nm diameter are ordered in a cross grid with a period of 1 µm.

    Project in the Business Area Photovoltaics, Topic: III-V and Concentrator Photovoltaics, Silicon Photovoltaics Fields of Work: III-V Epitaxy and Solar Cells, High-Efficiency Cell Fabrication and Analysis, Metallization and Patterning Duration: May 2015 - April 2019

    more info
  • Perovskite solar cells promise maximum efficiency. However, large-scale industrial production has so far failed due to the complexity of the spraying process. A reproducible, scalable process is intended to remedy this situation for the industry. In the “INTERVENTION” project, we investigated the optimization of spray coating by means of digital simulation of the process and experimental characterization of the materials. A research team developed data-driven solutions for systematic parameter optimization. The aim of the project was to achieve more efficient production on large wafer formats and faster optimization without time-consuming test series – a decisive step towards economically viable high-performance solar cells. | Duration: 01/2023 - 10/2025

    more info
  • PV-NIL

    Nanoimprint Lithography for Extremely Fine Solar Cell Structures

    © Fraunhofer ISE

    Fig. 1: Scanning electron micrograph of a structure that was transferred to silicon. The etching mask used was transferred in a single processing step by NIL. The hexagonal structure (honeycomb texture) has an integrated groove for later metallization.

    Project in the Business Area Photovoltaics; Topics: Silicon Photovoltaics, III-V- and Concentrator Photovoltaics and Emerging Photovoltaic Technologies; Fields of Work: High-Efficiency Cell Fabrication and Analysis, III-V Epitaxy and Solar Cells, Photon Management; Duration: April 2013 - March 2015

    more info
  • PeroLab Vacuum Processing.
    © Fraunhofer ISE

    PeroLab Vacuum Processing.

    Perovskite-silicon tandem solar cells have the potential to become the successor to the previously dominant silicon solar cell technology. To be able to transfer the developments at the lower technology maturity level (TRL 1-4) more rapidly into industrial production and thus accelerate the development of the next-generation cell technology together with the German and European photovoltaic industry, an independent technology platform for perovskite-silicon tandem technology is to be established in the Pero-Si SCALE project. This platform shall not only provide successful production technologies for cells and modules of the next generation but also an extensive characterization and analysis environment from the solar cell up to the PV power plant. | Duration: 05/2023 - 12/2026

    more info
  • © Fraunhofer ISE

    Sketch of a two-terminal perovskite silicon tandem solar cell with advanced optics using light trapping at the rear.

    Project in the Business Area Photovoltaics; Topics: Emerging Photovoltaic Technologies and Silicon Photovoltaics; Fields of Work: Dye and Perovskite Solar Cells, Tandem Solar Cells on Crystalline Silicon and High-Efficiency Cell Fabrication and Analysis; Duration: May 2016 - December 2019

    more info